JPH01321056A - Horizontal continuous casting method for metal tube and apparatus thereof - Google Patents

Abstract

PURPOSE:To suitably solidify a cast tube in mold device and to stably execute drawing cast by measuring drawing load to the cast tube in horizontal continuous casting, comparing with the reference drawing load and controlling drawing speed. CONSTITUTION:The drawing load measuring instrument 41 and the control unit 42 are arranged in the continuous casting apparatus 10. Then, working pressure of a hydraulic pump 16a in drawing roller device 16 is detected with the drawing load measuring instrument 41 to measure the drawing load of the cast tube 14. In the case the drawing load is larger than the reference drawing load, the control unit 42 controls a hydraulic pump driving control part 43 so that the drawing speed becomes large. Further, in the case the drawing load is smaller than the reference drawing speed, the hydraulic pump driving control part 43 is controlled so that the drawing speed becomes small.

Description

DETAILED DESCRIPTION OF THE INVENTION [Field of Industrial Application] The present invention relates to a method and apparatus for horizontal continuous casting of metal tubes.

[Prior art] A continuous casting method for metal tubes is disclosed in Japanese Patent Application Laid-open No. 80-54.
As described in Publication No. 255, a mold #J is disposed at the pouring port of a molten metal holding furnace, the molten metal is cooled in this molding device to form a cast tube, and this cast tube is drawn by a drawing roller device. Draw and cast.

[Problem R1 to be Solved by the Invention] By the way, the above-mentioned cast pipe needs to be appropriately solidified in a molding device before being drawn out.

■If the drawing speed is too slow, the solidification and shrinkage of the cast pipe in the mold will be excessive, causing excessive adhesive force and frictional force between the inner surface of the cast pipe and the core of the mold equipment, resulting in If the drawing speed is too fast, the solidification and shrinkage of the molten metal in the mold will not be sufficient, resulting in cracks, holes, and breakage in the cast tube (breakout). etc.

In addition, JP-A-80-15427 discloses that when continuously casting a solid bar, the surface temperature of the cast bar at the exit side of the mold device is measured, and if the surface temperature is higher than the reference temperature, the drawing waiting time is determined. A technique has been disclosed in which the temperature is increased to prevent hot water from leaking, and if the surface temperature is lower than the reference temperature, the withdrawal waiting time is shortened to prevent overcooling.

However, even if the above-mentioned conventional technology is applied to continuous casting of metal tubes, it is not possible to accurately estimate the contact state between the inner surface of the cast tube and the core portion of the mold device based only on the surface temperature state of the cast tube.

An object of the present invention is to appropriately solidify a cast pipe within a mold device and stably draw and cast the pipe.

[Means to solve the problem]

The present invention according to claim 1 provides a method for horizontal continuous casting of a metal tube, in which a molten metal contained in a molten metal holding furnace is solidified into a tubular shape in a molding device to form a cast tube, and the cast tube is pulled out. Measure the pullout load.

The pull-out control is performed so that if the pull-out load is larger than a predetermined standard pull-out load, the pull-out speed is increased, and if the pull-out load is smaller than the pre-determined reference pull-out load, the pull-out speed is decreased. It is.

The present invention as set forth in claim 2 is characterized in that the molten metal contained in the molten metal holding furnace is solidified into a tubular shape using a molding device to form a cast tube, and the cast tube is pulled out at a constant drawing speed during the drawing time. In the horizontal continuous casting method for metal tubes, which repeats one cycle of stopping drawing during the waiting period, the drawing load of the cast tube is measured, and in a steady state where the drawing load is approximately equal to a predetermined standard drawing load, the above drawing is performed. In a steady drawing process in which the time te and the waiting time tw are predetermined teo and two, and in a state where the pulling load is larger than the predetermined standard pulling load, the pulling time te is maintained at teo and the waiting time Lm is In the high-load pulling process, which is shorter than two, and in a state where the pulling load is smaller than a predetermined standard pulling load, the above-mentioned drawing time te is maintained at teo, and the above-mentioned waiting time tw is kept at t.
wo.

:, 'lClaim 3 Gyuhi 3 of the present invention is a mold device that is disposed at the pouring port of a molten metal holding furnace and solidifies the molten metal into a tubular shape to form a cast pipe, and a casting device formed by the mold device. In a horizontal continuous casting machine for metal tubes, which has a drawing roller device for drawing out the tube, a drawing load measuring device measures the drawing load of the cast tube by the drawing roller, and the measurement results of the drawing load measuring device are obtained. If the pull-out load is larger than a predetermined standard pull-out load, the pull-out speed is increased, and if the pull-out load is smaller than the predetermined reference pull-out load, the pull-out speed is decreased. The apparatus includes a device.

[Function] According to the present invention as set forth in claim 1.3, (1) If the measured pull-out load is larger than the predetermined reference pull-out load, 118yI
! It was determined that the solidification and shrinkage of the cast pipe inside the mold was excessive, causing excessive adhesion and frictional force between the inner surface of the cast pipe and the core of the mold equipment, and the mold equipment applied to the cast pipe. Increase the drawing speed to reduce the cooling that occurs. Also,
■If the measured pull-out load is smaller than the predetermined standard pull-out load.

It is determined that "the solidification shrinkage within the mold is not sufficient", and the drawing speed is reduced so that the mold device strengthens the cooling provided to the cast tube. Therefore, due to (1) [phase], the cast pipe can be appropriately solidified in the molding device and stably drawn and cast, resulting in breakout of the FJ pipe,
There is no possibility of damage to the mold device (core part).

Further, according to the present invention as set forth in claim 2, in a state where the measured pull-out load is greater than the predetermined reference pull-out load,
The solidification and shrinkage of the cast pipe in the mold is excessive, and the inner surface of the cast pipe is undergoing a high-load drawing process that is creating excessive adhesion and frictional force between it and the core of the mold device. Shorten the draw wait time so that the molding equipment provides less cooling to the cast tube. In addition, if the measured drawing load is smaller than the predetermined standard drawing load, it is determined that the drawing is in a low-load drawing process where solidification and shrinkage in the mold is not sufficient, and the mold equipment applies cooling to the cast pipe. Increase the extraction waiting time to strengthen the In addition, when the drawing operation of the cast pipe is performed intermittently with one cycle of drawing/stopping of drawing as in the present invention as set forth in claim 2, the cooling effect applied to the casting pipe by the mold device is performed at the time of stopping the drawing. (i.e. during the above-mentioned withdrawal waiting time), therefore, ■,
With (2), the cast pipe can be appropriately solidified in the mold equipment and drawn and cast stably, preventing breakouts of the cast pipe and damage to the mold fitting (core part). do not have.

[Embodiment] Fig. 1 is a control system diagram showing an embodiment of the present invention, Fig. 2 is a sectional view showing a #8 type device, and Fig. 3 is an end view showing a mold device.

As shown in FIG. 1, the continuous casting apparatus 10 includes a molten metal holding furnace 1.
A mold equipment fi 13 is attached to a casting opening 12 formed at the lower side of the mold 1. Continuous casting? 11O cools the molten metal using a 1g molding device 2113 to form a casting tube 14, which is drawn and cast.

The continuous casting device IO is equipped with a guide roller 15 that supports the casting tube 14 on the outlet side of the mold device 13, and
A drawing roller device 16 for drawing the cast tube 14 is provided. The pulling roller device 16 consists of a pinch roller 17 and a press roller 18. In addition, the drawing roller equipment GL
18 has a hydraulic motor 16B driven by a hydraulic pump 16A, and this hydraulic motor 16B drives a pinch roller 17, thereby applying a pulling force to the cast pipe 14.

As shown in FIGS. 2 and 3, the mold device 13 includes a mold 19 made of graphite or ceramics and a core 20 made of graphite or ceramics.

The mold 19 is hollow and has a core holding inner diameter part 21t at the end on the molten metal inflow side, and a tube outer surface forming inner diameter part 22 around the center axis of the mold extending substantially over the entire length excluding the core holding inner diameter part 21.

The core 20 is inserted into the mold 19, and the flange portion 2 is fitted into the core holding inner diameter portion 21 of the mold 19 at the molten metal outflow side end.
3, and is provided around the center axis of the mold over substantially the entire length excluding the flange portion 23 to form a tube forming passage 25 between the mold 19 and the tube outer surface molding inner diameter portion 22. Be prepared. Further, the core 20 is provided with molten metal injection passages 26 communicating with the tube forming passage 25 at each of a plurality of positions (fourth position 21 in this embodiment) around the mold center axis in the flange portion 23 . Each molten metal injection passage 26
The cross-sectional shape of the passage is arcuate. It is preferable that the thickness g of the joint portion 27 sandwiched between adjacent molten metal injection passages 26 be as small as possible to ensure strength, and that the passage area of each molten metal injection passage 26 be made larger.

That is, in the mold assembly fi 13, the flange portion 23 of the core 20 is fitted and fixed to the core holding inner diameter portion 21 of the mold 19, and the molten metal injection passage 26 and the tube forming passage 25 are communicated in a straight manner. Reference numeral 28 in FIG. 2 is a fixing pin between the mold 19 and the core 20.

Specifically, the mold assembly W113 includes a copper water cooling jacket 30 fitted to the molten metal outflow side end of the mold 19 via a graphite or ceramic liner 29, and a copper water cooling jacket body 30 fitted to the molten metal inflow side end of the mold 19. Insert rings 31 and 32 made of bricks are fitted, and the water cooling jacket body 3
An iron plate 33 is fitted between the insert ring 31 and the insert ring 31. As a result, the molding device 13 uses the water-cooled jacket body 30 as a cooling part for solidifying the molten metal, the insert ring 31 as a non-cooling part, and the insert ring 32 as a cooling part for solidifying the molten metal. It is used as a mounting part.

Further, the continuous casting apparatus 10 of this embodiment has a mold apparatus 13.
To prevent the molten metal flowing into the core from being supercooled,
A thank-you note 20A is provided at the molten metal inflow side end of the mold 1, and the end of the mold device 13 protrudes into the furnace.

However, continuous casting equipment ff1lo is a drawing load measuring equipment!
41 and a control device 142.

Pulling load measuring device! 41 detects the operating pressure of the hydraulic pump 16A constituting the drawing roller device 16, thereby causing the drawing roller device 16 to perform casting. Measure the pullout load of 14.

The control device 42 obtains the measurement result of the pull-out load measuring device 41, and controls the hydraulic pump drive control unit 43 so as to increase the pull-out speed if the pull-out load is larger than a predetermined reference pull-out load.
and (2) controls the hydraulic pump drive control unit 43 to reduce the extraction speed if the extraction load is smaller than a predetermined reference extraction load. Here, the drawing speed of the cast pipe 14 is fed back to the control device 42 via a drawing speed detector 44 connected to the output shaft of the hydraulic motor 16B.

That is, according to the above-mentioned continuous casting apparatus 1O, if the measured drawing load is larger than the predetermined standard drawing load, "the solidification shrinkage of the casting pipe 14 in the mold apparatus 13 is excessive, and the inner surface of the casting pipe 14 It was determined that "excessive adhesive force and frictional force were generated between the mold device 13 and the core 20 of the mold device 13," and the drawing speed was increased so as to weaken the cooling that the mold device ff113 applied to the casting tube 14. do. ■If the measured pull-out load is smaller than the predetermined standard pull-out load,
It was determined that the solidification shrinkage was not sufficient, and the mold was installed! 113 reduces the drawing speed so as to increase the cooling provided to the cast tube 14. Therefore,■.

As a result of (1), the T4 tube 14 can be appropriately solidified inside the mold device 113 and can be drawn and cast stably, resulting in breakout of the cast tube 14 and damage to the core 20 of the mold device 13. Never.

In the continuous casting apparatus IO of the above embodiment, the drawing roller device M is controlled by the intermittent drawing control by the control device 42.
16, the casting tube 14 is pulled out at a constant drawing speed for a drawing time (te), and the waiting time after this drawing is (te).
tw ) can be repeated as one cycle. At this time, the control device 42 obtains the measurement result of the above-mentioned drawing load measuring device g141, and controls the casting tube 14 to be pulled out in one of the steady drawing process, high load drawing process, or low load drawing process. The drawing speed of 14 is controlled.

Each of the above-mentioned drawing processes is as follows.

(2) The steady drawing process is a steady state in which the drawing load is approximately equal to a predetermined standard drawing load, and the drawing time te and waiting time tw are set to predetermined teo and two.

(2) In the high-load drawing process, the drawing time te is maintained at teo and the waiting time tw is made shorter than two in a state where the drawing load is greater than a predetermined standard drawing load.

(2) The low-load pulling process is a process in which the pulling load is smaller than a predetermined standard pulling load, the pulling time is maintained at telteo, and the waiting time tw is made longer than two.

That is, in the continuous casting apparatus 1110 described above.

■ In a state where the measured drawing load is larger than the predetermined standard drawing load, the solidification shrinkage of the casting tube 14 in the molding device 13 becomes excessive, and the inner surface of the casting tube 14 is between the core 20 of the molding device 13. Excessive contact force, L'l! It is a high-load drawing process that is causing friction force,'' and the mold device 13
The waiting time tw is set such that the cooling applied to the casting tube 14 is weakened.
shorten.

In addition, if the measured drawing load is smaller than the predetermined standard drawing load, it is determined that the mold device 13 is in a low-load drawing process where solidification and shrinkage is not sufficient, and the mold device 13 The waiting time tw is increased so as to strengthen the cooling applied to the system.

In addition, when the drawing operation of the cast pipe 14 is performed intermittently with one cycle of drawing/stopping as described above,
The cooling effect that the mold device 13 imparts to the casting tube 14 is performed when the drawing is stopped (that is, during the above-mentioned drawing waiting time tw). It is possible to solidify the tube and perform stable pultrusion casting, and the breakout of the cast pipe 14
, the core 20 of the molding device will not be damaged.

According to the experimental results of the present inventor, when casting tubes [32A, 65A, 80A, wall thickness 4.2 to 4.5 cm] were continuously cast using the above-mentioned continuous casting apparatus 10, appropriate standards were met. The pull-out load was approximately 42 kg/cm2, and it was recognized that if the pull-out load was larger or smaller than this, the casting troubles described above would occur.

[Effects of the Invention] As described above, according to the present invention, a cast pipe can be appropriately solidified in a mold device and stably drawn and cast.

[Brief explanation of the drawing]

FIG. 11 is a control system diagram showing one embodiment of the present invention, FIG. 2 is a sectional view showing a molding device, and FIG. 3 is an end view showing the molding device. 10... Continuous casting device, 11... Molten metal holding furnace. 12... Casting port, 13... Mold device. 14... Casting pipe, 16... Drawing roller device, 20... Core, 41... Drawing load measuring device, 42... Control device. 44...Drawing speed detector. Agent Patent Attorney Osamu Shiokawa First drawing! Figure 2

Claims (3)

[Claims] (1) In a horizontal continuous casting method for metal tubes, in which the molten metal contained in the molten metal holding furnace is solidified into a tubular shape using a molding device to form a cast tube, and the cast tube is pulled out, the pull-out load of the cast tube is measured; The pull-out control is performed such that if the pull-out load is larger than a predetermined standard pull-out load, the pull-out speed is increased, and if the pull-out load is smaller than the pre-determined reference pull-out load, the pull-out speed is decreased. Horizontal continuous casting method for metal tubes. (2) Solidifying the molten metal contained in the molten metal holding furnace into a tubular shape using a molding device to form a cast pipe, drawing out the cast pipe at a constant drawing speed during the drawing time, and stopping the drawing during the waiting period after this drawing. In the horizontal continuous casting method for metal tubes, which repeats 1 cycle, the pull-out load of the cast tube is measured, and in a steady state where the pull-out load is approximately equal to a predetermined standard pull-out load, the above-mentioned pull-out time te and waiting time tw are predetermined t
a steady drawing process in which eo and two are set; and a high-load drawing process in which the drawing time te is maintained at teo and the waiting time tw is shorter than two in a state where the drawing load is greater than a predetermined standard drawing load; When the pull-out load is smaller than the predetermined standard pull-out load, the pull-out time te is
o, and a low-load drawing process in which the waiting time tw is longer than two. (3) It has a mold device that is installed at the pouring port of the molten metal holding furnace and solidifies the molten metal into a tubular shape to form a cast tube, and a drawing roller device that pulls out the cast tube formed by the mold device. In the horizontal continuous casting machine for metal tubes, we have a pull-out load measuring device that measures the pull-out load of the cast tube by the pull-out roller device, and we have obtained the measurement results of the pull-out load measuring device and determined that the pull-out load is lower than the predetermined standard pull-out load. a control device for controlling the pulling so that if the pulling load is larger than the predetermined standard pulling load, the drawing speed is increased; if the pulling load is smaller than a predetermined standard pulling load, the pulling speed is decreased. Horizontal continuous casting equipment for pipes.